Impregnating paper for insulation of electric cables and apparatus therefor



C. J. BEAVER IMPREGNATING PAPER FOR INSULATION OF ELECTRIC April 1, 1930.

CABLES AND APPARATUS THEREFOR Filed March 16, 1929 2 Sheets-Sheet 1 Zia Z A TTORNEY;

ril 1, 19m

C. J. BEAVER IMPREGNATING PAPER FOR INSULATION OF ELECTRIC CABLES AND APPARATUS THEREFOR Filed March 16, 1929 2 Sheet h 2 NVENTOR.

ATTO

Patented Apr. 1, 1930 UNITEDSVTATES PATENT OFFICE CHAELEs J MES BEAVER, oEEownoN, ENGLAND, ASSIGNOR To w. T. eLovEE AND OMPANY LIIIITEnoE MANCHESTER, ENGLAND IMPREGNATING PAPER FOR INSULATION or ELECTRIC GABLES AND APPARATUS THEREFOR Application filed March 16, 1929, Serial No. 847,700, and in Great Britain March 7, 1928.

This invention has reference to the impregnating of paper for the insulation of electric cables. I

In the impregnating of paper for the purpose aforesaid it is of'the highest importance to extract so far as possible all the airand moisture from the body of the paper.

Heretofore it has been the practice to conduct the paper from a drum into a tank containing liquid compound with which it is to be saturated,'round rollers-in such tank, and eventually out of the tank and on to another drum on which it is wound, passing scrapers and such like devices, on its journey to the '15 last drum, and in some cases the paper is carried over hot rollers before being immersed in the compound with the object of causing air in the crevices thereof to expand and dissipate before the paper enters the compound. According to this invention the whole of the process of saturating is carried out in a vacuum, thus assisting in the setting free of all air from the body of the paper.

For this purpose we construct apparatus comprising a lidded tank, the joints being capable of being made airtight, adapted tocontain molten compound, into and through which the paper travels while being drawn off of a drum, and rewound'on another drum,

with-means whereby the paper is subjected to the effect of the vacuum before being immersed in thecompound and preferably also while being so subjected is carried over hot rollers.

An example of apparatus made in accordance with this invention is illustrated in the accompanying drawings. Fig. 1 is a side view of the apparatus. Fig. 2 a front view looking in the direction of the arrow shown to the left of Fig. 1,'Fig. 3 is a plan view.

Figures 4 and 5. are respectively a vertical section and a plan view of the supplemental tank and seating device, described on an enlarged scale and Fig. 6 a vertical section of a part on an enlarged scale.

a is an air-tight chamber with an extension at. The extension a has a rectangular aperture or opening on the top for the purpose of introducing the drum of paper to be in- 59 sulated and such aperture is provided with a cover or lid a adapted to hermetically sealthe hole. The main part of the tank has an elongated aperture at the top provided with a cover a adapted to hermetically seal such aperture. A metal frame a on which are mounted three rollers a being guides for the paper as it travels through the liquid insulating material. The frame a is so arranged that on removing the cover the frame and rollers can be withdrawn from the tank for the purpose of manipulating the paper, and from the sides of the tank webs are projected to guide the frame to its correct position. (L6 are doors to an opening in the front of the main part of the tank also adapted when closed to hermetically seal the opening. a is. a wall extending right across the main tank and from the bottom to near the top as illustrated. a are rollers to guide the paper up and down the chamber before being immersed in the insulating material. a is an elongated slot in the roof of the tank a, through which the paper issues, a are three guide rollers, a are steam pipes for'heating the rollers a and a is an orifice adapted for the attachment of the vacuum pump. 7; is a narrow elongated tank open to the atmosphere, 6 are flat oblong rubber blocks held in position, by holders 6 The positions of the rubber blocks are adjustable by the threaded rods 6 located in the brackets b and engaging respectiv'ely the blocks 6 which are secured to through its interior, and e is a driving pulley on the same shaft for the purpose of driving the roller 0 through the pulley '0 f are scraping knives, each connected to a steam pipe for the purpose of being kept hot. 9 are steam pipes through which steam is continuously passed in'order to keep the liquid in the tank a and in the trough C and also the scraping knives f at the required temperature. 72. is a pump driven by the pulley k and which is driven by band k adapted to pump liquid from the tank a via the pipe h into the tank I). h is an over-flow pipe carrying liquid from 100 can pass from time to time by the opening of the valve h in the tank a. i is a pump adapti ed to extract air from the inside of the tank a.

j is a drum carrying the paper to be impregnated. i I

The apparatus is driven through the pulley k on the shaft of which isthe gear wheel 10 in mesh with the gear wheel d through which the receiving mandrel d is driven.

The shaft (Z and the mandrel (Z are rotatably connected by means of a readily detachable coupling (i a The gear wheel (1 is frictionally'mounted on the shaftd so as to accommodate the increase of diameter as the paper is wound up on the mandrel d.

The chain (1 on the sprocket d mounted on the shaft d drives the chain wheel (2?, and the band on the pulley 6 drives the pulley '6 The part of the machine comprising the paper after it leaves the tank I), the haul ofi' wheel, and the receiving mandrel are all enclosed in a suitable room ofchamber m diagrammatically shown in Fig. 1 kept'in a suitable atmosphere and at the required tempera ture for the purposes of preventing -the re-absorption of atmospheric moisture. The parts designated 11 n n n, are gated openings in the walls of chamber m.

The apparatus is worked and functions as follows By opening the doors and lids the drum 7' can be mounted on bearings, the paper placed around the guides a and rollers a and a and through the slot a past the scraping knives 9' over the roller 0 around the haul olf roller e and on to the receiving mandrel (Z all as indicated by the arrows. It will be realizedthat when the lid 11 is open the frames a and the rollers (13 are easily accessible.

The rubber blocks on either side of the slot a are closed up to the paper and fixed in position, the doors and lids are then closed down to render the inside of the tank hermetically sealed, the heating steam is turned on, the

pump worked to extract the air from inside the chamber a, the pump it started to work,

started.

and the'valve h "of the chamber its set to maintain a predetermined heat of liquid above it. i

The tank a when the paperis in position is filled on the right side of the wall at up to the level indicated by the dotted line with the impregnating fluid material and a quantity of the'like fluid material is poured into It will be obvious that a quantity of the impregnating liquid will leak past the paper or fabric issuing from the slot (1", from the paper sheet. The driving is then tank 6 into the tank a. This will be constantly rectified by the pump it which is re-delivering liquid from ,the tanka into the tank 6 and in case of any over-flow from the tank 6 the liquid will be re-delivered to the tank a through the pipe k and the valve It.

.What I claim is Apparatus for the purpose of impregnatmg a long strip of fibrous material with elec-' rial in a liquid form and to be hermetically sealed, means for producing and maintaining a vacuum in such tank, a slot belng formed in the exitend of such a tank adapted for passing a strip of materialout of the tank, a supplemental tank disposed above said first mentioned tank and communicating therei with through said slot and adapted to contain a quantity of the insulating material, a

pump adapted to pump liquid from the main tank into the supplemental tank, an overflow from the supplemental tank discharging through an adjustable valve into the main tankand means for drawing thepaper from a drum through the said liquid and out of i the main tank via the slot and supplemental tank. I

In testimony whereof I have hereunto affixed my signature.

CHARLES JAMES BEAVER. 

